On 26 August 2015 at 14:03, tony duell <a...@p850ug1.demon.co.uk> wrote: > I've only ever seen the ones with 3 position levers, but from reading the > manuals I think the 3 position levers are manual control models and > 4 position levers are automatic control models (with extra levers and > swtiches in the stunt box to start and stop the reader using XON/XOFF > characters) > You are correct. The four position reader control lever are for machines that use DC1/DC3 (XON/XOFF) to control the reader automatically.
> The 3 position lever models (manual control) can certainly take the reader > run relay and be used with PDP8s and PDP11s. > If I recall correctly; weren't the "preferred" versions of the 33ASR for use where the reader was controlled by the computer the 3-position manual reader control models? Since the reader won't run unless the computer is asserting the reader control lines anyway, and with such hardware flow control XON/XOFF automatic control become redundant. Regards, Christian -- Christian M. Gauger-Cosgrove STCKON08DS0 Contact information available upon request.
